Clinically significant drug interactions at clinical doses are considered unlikely due to the low plasma concentrations achieved after inhaled dosing.
Interaction with beta-blockers – Beta2-adrenergic blockers may weaken or antagonise the effect of beta2-adrenergic agonists, such as vilanterol. Cardioselective beta-blockers should be considered if a beta-blocker is required.
Interaction with CYP3A4 inhibitor – Fluticasone furoate and vilanterol are rapidly cleared by extensive first-pass metabolism mediated by enzyme CYP3A4.
Caution is advised when co-administering with strong CYP3A4 inhibitors like;
- Cobicistat-containing products.
Concomitant hypokalaemic treatment with methylxanthine derivatives, steroids, or non-potassium-sparing diuretics may potentiate the possible hypokalaemic effect of beta2-adrenergic agonists, therefore caution should be exercised.